A wireless power system typically comprises a wireless power transmitter and a wireless power receiver. The wireless power transmitter transmits power wirelessly using a transmitter coil. Through the transmitter coil, the wireless power transmitter creates an electromagnetic field in a coupling region for providing energy transfer to the wireless power receiver. The wireless power receiver comprises a receiver coil that picks up the electromagnetic field. A voltage is induced in a receiver coil due to the electromagnetic field emanating from the transmitter coil. In the coupling region, power is transferred from the wireless power transmitter to the wireless power receiver.
In conventional wireless power systems, there is only one way communication from the wireless power receiver to the wireless power transmitter. This communication link is used by the wireless power receiver to relay information, for example, messages to increase power being transmitted, decrease power being transmitted, maintain the same amount of power being transmitted, terminate transmission of power, etc., to the wireless power transmitter. In conventional wireless power systems, there is no communication link from the wireless power transmitter to the wireless power receiver. As a result, the transmitter cannot query and obtain any information from the receiver.
With a communication link from the transmitter to the receiver, communication between the devices is bi-directional. This allows the construction of smarter, differentiated wireless power systems. For example, the transmitter can challenge and authenticate the identity of the receiver. If the receiver is a “known” device, the transmitter can turn on certain algorithms or reconfigure itself to enable higher power delivery or allow more spatial separation. The transmitter could also reconfigure the receiver to maintain stable power delivery. Therefore, there is a long felt but unresolved need for a method and system that establishes a communication link from a wireless power transmitter to a wireless power receiver.